This is the large Neotech mute bag. Marked for trombone, but also is the perfect fit for cone style tunable french horn mutes (i.e. Maslet). Fits most trombone straight and practice mutes. Made from a durable neoprene. It has a drawstring closure for fast, easy access. You can attach this mute pouch to your instrument case via the snaphook or Velcro clasps.